Polycarbonate resin and manufacturing process thereof

ABSTRACT

A polycarbonate resin which shows a high content of biogenic matter and has excellent heat resistance, heat stability and moldability, and a manufacturing process thereof. The polycarbonate resin contains a recurring unit represent by the following formula (1) as the major constituent, and has (i) a specific viscosity of a solution prepared by dissolving 0.7 g of the resin in 100 ml of methylene chloride at 20° C. of 0.20 to 0.45, (ii) a glass transition temperature (Tg) of 150 to 200° C., and (iii) a 5% weight loss temperature (Td) of 330 to 400° C.

TECHNICAL FIELD

The present invention relates to a novel polycarbonate resin and amanufacturing process thereof. More specifically, it relates to apolycarbonate resin containing a unit which can be derived from a sugaras biogenic matter and having high heat resistance and heat stabilityand excellent moldability and to a manufacturing process thereof.

BACKGROUND OF THE ART

Polycarbonate resins are polymers obtained by combining aromatic oraliphatic dioxy compounds by means of a carbonate. Out of these, apolycarbonate resin obtained from 2,2-bis(4-hydroxyphenyl)propane(commonly called “bisphenol A”) (may be referred to as “PC-A”hereinafter) is used in many fields because it has high transparency andheat resistance and excellent mechanical properties such as impactresistance.

Polycarbonate resins are generally manufactured from raw materialsobtained from oil resources. The depletion of oil resources is nowapprehended, and the manufacture of a polycarbonate resin from a rawmaterial obtained from biogenic matter such as plants is desired. Apolycarbonate resin obtained from an ether diol raw material which canbe manufactured from a sugar as a biomass material obtained frombiogenic matter is now under study.

For example, an ether diol represented by the following formula (2) iseasily formed from a sugar or starch.

This ether diol has three known stereoisomers represented by thefollowing formulas (3) to (5). They are 1,4:3,6-dianhydro-D-sorbitol (tobe referred to as “isosorbide” hereinafter in this text) represented bythe following formula (3), 1,4:3,6-dianhydro-D-mannitol (to be referredto as “isomannide” hereinafter in this text) represented by thefollowing formula (4), and 1,4:3,6-dianhydro-L-iditol (to be referred toas “isoidide” hereinafter in this text) represented by the followingformula (5).

Isosorbide, isomannide and isoidide are obtained from D-glucose,D-mannose and L-idose, respectively. For example, isosorbide can beobtained by hydrogenating D-glucose and dehydrating it with an acidcatalyst.

Out of the above ether diols, it has been studied that isosorbide ismainly used as a monomer to be introduced into a polycarbonate.

Patent document 1 discloses a homopolycarbonate resin having a meltingpoint of 203° C. which is obtained by a molten ester interchange method.However, this polymer is not satisfactory in terms of mechanicalproperties.

Non-patent document 1 discloses a homopolycarbonate resin having a glasstransition temperature of 166° C. which is obtained by the molten esterinterchange method using zinc acetate as a catalyst. However, thispolycarbonate resin is not satisfactory in terms of heat stabilitybecause it has a thermal decomposition temperature (5% weight losstemperature) of 283° C.

Non-patent document 2 discloses a homopolycarbonate resin obtained fromisosorbide and bischloroformate by interfacial polymerization. However,this polycarbonate resin is unsatisfactory in terms of heat resistancebecause it has a glass transition temperature of 144° C.

Patent document 7 discloses a polycarbonate resin having a glasstransition temperature of 170° C. or higher which is manufactured fromisosorbide and diaryl carbonate in the presence of a tin catalyst.However, as this polycarbonate resin has a high glass transitiontemperature, its molding temperature becomes high in order to obtain amolded product from this by injection molding, thereby promoting thethermal decomposition of the polymer. Since this polycarbonate resin hasa thermal decomposition temperature (5% weight loss temperature) ofaround 300° C., it has room to improve its heat stability.

To improve the heat resistance and heat stability of a polycarbonateresin, it is conceivable that it is copolymerized with anotherbishydroxy compound. However, when an aromatic bisphenol derived frompetroleum is used, it is against the original purpose that biogenicmatter is used (patent document 2, patent document 6 and non-patentdocuments 3 to 5). There are many aliphatic diols which are derived frompetroleum (patent documents 3 to 5), and diols which are biogenic matterare limited to diols having a relatively small number of carbon atomssuch as propanediol and butanediol. The boiling points of thesealiphatic diols which are biogenic matter are lower than that ofisosorbide, and the aliphatic diols are distilled off from a reactionsystem when polymerization is carried out by the molten esterinterchange method. Further, heat stability becomes unsatisfactory.

Consequently, to keep the high proportion of the biogenic matter, ahomopolycarbonate resin of isosorbide or copolymerization with anotheraliphatic diol which is biogenic matter is suitable. However, apolycarbonate resin having a high content of biogenic matter, which issatisfactory in terms of both heat stability and heat resistance, hasnot been reported yet.

(patent document 1) English Patent Application No. 1079686(patent document 2) German Patent Application No. 2938464(patent document 3) JP-A 2003-292603(patent document 4) WO2004/111106(patent document 5) JP-A 2006-232897(patent document 6) JP-A 56-110723(patent document 7) WO2007/013463(non-patent document 1) “Journal of Applied Polymer Science”, 2002, vol.86, p. 872-880(non-patent document 2) “Macromolecules”, 1996, vol. 29, p. 8077-8082(non-patent document 3) “Macromolecular Chemistry and Physics”, 1997,vol. 198, p. 2197-2210(non-patent document 4) “Journal of Polymer Science: Part A”, 1997, vol.35, p. 1611-1619(non-patent document 5) “Journal of Polymer Science: Part A”, 1999, vol.37, p. 1125-1133

DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide a polycarbonateresin which has a high content of biogenic matter and is excellent inheat resistance, heat stability and moldability. It is another object ofthe present invention to provide a process of manufacturing thepolycarbonate resin.

The inventors of the present invention have conducted intensive studiesto attain the above objects and have found that a polycarbonate resinhaving excellent heat resistance, heat stability and moldability isobtained by using at least one compound selected from the groupconsisting of a nitrogen-containing basic compound, alkali metalcompound and alkali earth metal compound as a polymerization catalystand employing specific polymerization conditions. The present inventionhas been accomplished based on this finding.

That is, the present invention provides the following.

1. A polycarbonate resin containing a recurring unit represented by thefollowing formula (1) as the major constituent, wherein

(i) the specific viscosity of a solution prepared by dissolving 0.7 g ofthe resin in 100 ml of methylene chloride at 20° C. is 0.20 to 0.45;

(ii) the glass transition temperature (Tg) of the resin is 150 to 200°C.; and

(iii) the 5% weight loss temperature (Td) of the resin is 330 to 400° C.

2. The polycarbonate resin according to the above item 1 which containsthe recurring unit represented by the formula (1) in an amount of morethan 98 mol % and 100 mol % or less.3. The polycarbonate resin according to the above item 1, wherein thespecific viscosity of a solution prepared by dissolving 0.7 g of theresin in 100 ml of methylene chloride at 20° C. is 0.20 to 0.37.4. The polycarbonate resin according to the above item 1 which has aglass transition temperature (Tg) of 150 to 168° C.5. The polycarbonate resin according to the above item 1 which has anumber average molecular weight of 1.2×10⁴ to 2.0×10⁴.6. The polycarbonate resin according to the above item 1 which has abiogenic matter content measured in accordance with ASTM D6866 05 of 83to 100%.7. The polycarbonate resin according to the above item 1, wherein therecurring unit represented by the formula (1) is a unit derived fromisosorbide.8. The polycarbonate resin according to the above item 1, wherein therecurring unit represented by the formula (1) is a combination of 75 to99 mol % of a unit derived from isosorbide and 25 to 1 mol % of a unitderived from isomannide and/or isoidide.9. A process of manufacturing a polycarbonate resin by reacting a diolcomponent (component A) with a diester carbonate (component B), wherein

(i) the diol component (component A) contains an ether diol representedby the following formula (2) as the major constituent,

and the process comprises the steps of:

(ii) thermally reacting these components at normal pressure in thepresence of at least one polymerization catalyst selected from the groupconsisting of a nitrogen-containing basic compound, alkali metalcompound and alkali earth metal compound; and

(iii) thermally reacting these components at 180 to 280° C. underreduced pressure.

10. The manufacturing process according to the above item 9, wherein theratio of the diester carbonate (component B) to the diol (component A)(B/A) is 1.02 to 0.98.11. The manufacturing process according to the above item 9, wherein thediol component (component A) contains a compound represented by theformula (2) in an amount of more than 98 mol % and 100 mol % or less.12. The manufacturing process according to the above item 9, wherein thecompound represented by the formula (2) is isosorbide.13. The manufacturing process according to the above item 9, wherein thecompound represented by the formula (2) consists of 75 to 99 mol % ofisosorbide and 25 to 1 mol % of isomannide and/or isoidide.14. The manufacturing process according to the above item 9, wherein thediester carbonate (component B) is diphenyl carbonate.15. The manufacturing process according to the above item 9, wherein thepolymerization catalyst is a combination of a nitrogen-containing basiccompound and an alkali metal compound.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in detail hereinunder.

[Polycarbonate Resin]

The polycarbonate resin of the present invention contains a recurringunit represented by the following formula (1) as the major constituent.

The content of the recurring unit represented by the formula (1) ispreferably more than 98 mol % and 100 mol % or less. The polycarbonateresin is particularly preferably a homopolycarbonate resin having acontent of the recurring unit of the formula (1) of 100 mol %. Anotherunit is a unit derived from an aliphatic diol such as propanediol orbutanediol or an aromatic diol such as bisphenol A.

The recurring unit represented by the formula (1) is preferably a unitderived from isosorbide.

The recurring unit represented by the formula (1) may be a combinationof a unit derived from isosorbide and a unit derived from isomannideand/or isoidide. In this case, the content of the unit derived fromisosorbide in the recurring unit represented by the formula (1) ispreferably 75 to 99 mol %, more preferably 80 to 99 mol %, much morepreferably 90 to 99 mol %. The content of the unit derived fromisomannide and/or isoidide in the recurring unit represented by theformula (1) is preferably 25 to 1 mol %, more preferably 20 to 1 mol %,much more preferably 10 to 1 mol %. Therefore, it is preferred that therecurring unit represented by the formula (1) should consist of 75 to 99mol % of the unit derived from isosorbide and 25 to 1 mol % of the unitderived from isomannide and/or isoidide.

When the unit derived from isomannide and/or isoidide is contained inthe unit derived from isosorbide, the obtained polycarbonate resin hasmuch higher heat resistance than that of a homopolycarbonate resinhaving the same specific viscosity as that of the above polycarbonateresin, which is composed of only the unit derived from isosorbide. Apolycarbonate resin composed of the unit derived from isosorbide and theunit derived from isomannide is particularly preferred.

A solution prepared by dissolving 0.7 g of the polycarbonate resin ofthe present invention in 100 ml of methylene chloride has a specificviscosity of 0.20 to 0.45 at 20° C. The specific viscosity is preferably0.20 to 0.37, more preferably 0.22 to 0.34. When the specific viscosityis lower than 0.20, it is difficult to provide sufficiently highmechanical strength to the obtained molded product. When the specificviscosity is higher than 0.45, melt flowability becomes too high,whereby the melt temperature required for molding becomes higher thanthe decomposition temperature disadvantageously.

The glass transition temperature (Tg) of the polycarbonate resin of thepresent invention is 150 to 200° C. The glass transition temperature(Tg) is preferably 150° C. or higher and lower than 170° C., morepreferably 150 to 168° C., much more preferably 160 to 168° C. When Tgis lower than 150° C., the obtained polycarbonate resin deteriorates inheat resistance (especially heat resistance by moisture absorption) andwhen the temperature is higher than 200° C., the polycarbonate resindeteriorates in melt flowability at the time of molding.

The 5% weight loss temperature (Td) of the polycarbonate resin of thepresent invention is 330 to 400° C. The 5% weight loss temperature ispreferably 340 to 390° C., more preferably 350 to 380° C. When the 5%weight loss temperature falls within the above range, the decompositionof the resin rarely occurs during melt molding advantageously.

Further, the number average molecular weight (Mn) of the polycarbonateresin of the present invention is preferably 1.2×10⁴ to 2.2×10⁴, morepreferably 1.2×10⁴ to 2.0×10⁴, much more preferably 1.25×10⁴ to 2.0×10⁴.When the number average molecular weight (Mn) falls within the aboverange, the polycarbonate resin has excellent mechanical strength andmoldability.

The content of biogenic matter measured in accordance with ASTM D6866 05in the polycarbonate resin of the present invention is preferably 83 to1001, more preferably 84 to 100%.

The melt viscosity measured with a capillary rheometer at 250° C. of thepolycarbonate resin of the present invention is preferably 0.4×10³ to2.4×10³ Pa·s, more preferably 0.4×10³ to 1.8×10³ Pa·s at a shear rate of600 sec⁻¹. When the melt viscosity falls within the above range, thepolycarbonate resin has excellent mechanical strength and highmoldability without the formation of a silver streak during molding.

[Process of Manufacturing Polycarbonate Resin]

The polycarbonate resin of the present invention can be obtained bymixing together a diol and a diester carbonate and carrying out meltpolymerization while an alcohol or phenol formed by an ester interchangereaction is distilled off at a high temperature under reduced pressure.

That is, the manufacturing process of the present invention is tomanufacture a polycarbonate resin by reacting a diol (component A) witha diester carbonate (component B),

wherein

(i) the diol component (component A) contains an ether diol representedby the following formula (2) as the major constituent,

and the process comprises the steps of:

(ii) thermally reacting these components at normal pressure in thepresence of at least one polymerization catalyst selected from the groupconsisting of a nitrogen-containing basic compound, alkali metalcompound and alkali earth metal compound; and

(iii) thermally reacting these components at 180 to 280° C. underreduced pressure.

(Diol)

The diol contains an ether diol represented by the following formula (2)as the major constituent.

The diol contains a compound represented by the formula (2) in an amountof preferably more than 98 mol % and 100 mol % or less, more preferably100 mol %.

Examples of the ether diol represented by the formula (2) includeisosorbide, isomannide and isoidide represented by the above formulas(3), (4) and (5), respectively. The compound represented by the formula(2) is preferably isosorbide (1,4;3,6-dianhydro-D-sorbitol).

The compound represented by the formula (2) may be a combination ofisosorbide and isomannide and/or isoidide. In this case, the content ofisosorbide in the compound represented by the formula (2) is preferably75 to 99 mol %, more preferably 80 to 99 mol %, much more preferably 90to 99 mol %. The content of isomannide and/or isoidide in the compoundrepresented by the formula (2) is preferably 25 to 1 mol %, morepreferably 20 to 1 mol %, much more preferably 10 to 1 mol %. Therefore,the compound represented by the formula (2) consists of 75 to 99 mol %of isosorbide and 25 to 1 mol % of isomannide and/or isoidide.

Ether diols derived from these sugars are also obtained from biomass inthe natural world and so-called “regenerable resources”. Isosorbide isobtained by hydrogenating D-glucose obtained from starch and dehydratingthe hydrogenated D-glucose. Other ether diols are obtained by a similarreaction except starting materials.

(Diester Carbonate)

The diester carbonate is an ester such as an aryl group or aralkyl grouphaving 6 to 12 carbon atoms whose hydrogen atom may be substituted, oran alkyl group having 1 to 4 carbon atoms. Examples of the diestercarbonate include diphenyl carbonate, bis(chlorophenyl)carbonate,m-cresyl carbonate, dinaphthyl carbonate, bis(diphenyl)carbonate,dimethyl carbonate, diethyl carbonate and dibutyl carbonate. Out ofthese, diphenyl carbonate is preferred from the viewpoints of reactivityand cost.

The molar ratio of the diester carbonate (component B) to the diol(component A) is preferably 1.02 to 0.98, more preferably 1.01 to 0.98,much more preferably 1.01 to 0.99. When the (B/A) molar ratio is higherthan 1.02, the ester carbonate residue serves to cap the terminal,whereby a sufficiently high degree of polymerization may not be obtaineddisadvantageously. When the molar ratio of the diester carbonate islower than 0.98, a sufficiently high degree of polymerization is notobtained.

(Polymerization Catalyst)

The polymerization catalyst is at least one selected from the groupconsisting of a nitrogen-containing basic compound, alkali metalcompound and alkali earth metal compound.

Examples of the alkali metal compound include sodium hydroxide,potassium hydroxide, sodium carbonate, potassium carbonate, sodiumhydrogencarbonate, and sodium salts and potassium salts of a diphenol.Examples of the alkali earth metal compound include calcium hydroxide,barium hydroxide and magnesium hydroxide. Examples of thenitrogen-containing basic compound include tetramethylammoniumhydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide,trimethylamine and triethylamine. They may be used alone or incombination of two or more. A combination of a nitrogen-containing basiccompound and an alkali metal compound is particularly preferred.

The amount of the polymerization catalyst is preferably 1×10⁻⁹ to 1×10⁻³equivalent, more preferably 1×10⁻⁸ to 5×10⁻⁴ equivalent based on 1 molof the diester carbonate (component B). The reaction system ispreferably kept in an inert gas atmosphere such as nitrogen for the rawmaterials, reaction mixture and reaction product. Other inert gasesother than nitrogen include argon. Additives such as an antioxidant maybe added as required.

The reaction temperature is preferably as low as possible in order tosuppress the decomposition of the ether diol and obtain a resin which israrely colored and has a high viscosity. The polymerization temperatureis in the range of preferably 180 to 280° C., more preferably 180 to260° C. in order to promote the polymerization reaction properly. Thefinally reached temperature of the reaction is preferably 235 to 265°C., more preferably 240 to 260° C.

A process comprising the steps of heating an ether diol and a diestercarbonate at normal pressure to pre-react them in the initial stage ofthe reaction and gradually reducing the inside pressure of the system toabout 1.3×10⁻³ to 1.3×10⁻⁵ MPa to facilitate the distillation-off of theformed alcohol or phenol in the latter stage of the reaction ispreferred. The reaction time is generally about 1 to 4 hours.

A catalyst deactivator may be added to the polycarbonate resin. Knowncatalyst deactivators may be used. Out of these, ammonium salts andphosphonium salts of sulfonic acid are preferred, and ammonium salts andphosphonium salts of dodecylbenzenesulfonic acid such astetrabutylphosphonium salts of dodecylbenzenelsulfonic acid, andammonium salts and phosphonium salts of paratoluenesulfonic acid such astetrabutylammonium salts of paratoluenesulfonic acid are more preferred.Methyl benzenesulfonate, ethyl benzenesulfonate, butyl benzenesulfonate,octyl benzenesulfonate, phenyl benzenesulfonate, methylparatoluenesulfonate, ethyl paratoluenesulfonate, butylparatoluenesulfonate, octyl paratoluenesulfonate and phenylparatoluenesulfonate are preferred as the ester of sulfonic acid. Out ofthese, tetrabutylphosphonium salts of dodecylbenzenesulfonic acid aremost preferred. The amount of the catalyst deactivator is 0.5 to 50mols, preferably 0.5 to 10 mols, more preferably 0.8 to 5 mols based on1 mol of the polymerization catalyst selected from an alkali metalcompound and/or an alkali earth metal compound.

Function adding agents such as a heat stabilizer, stabilizing aid,plasticizer, antioxidant, optical stabilizer, nucleating agent, heavymetal inactivating agent, flame retardant, lubricant, antistatic agentand ultraviolet absorber may be added to the polycarbonate resin of thepresent invention according to application purpose.

The polycarbonate resin of the present invention may be combined with anorganic or inorganic filler or fiber to be used as a complex accordingto application purpose. Examples of the filler include carbon, talc,mica, wollastonite, montmorillonite and hydrotalcite. Examples of thefiber include natural fibers such as kenaf, synthetic fibers, glassfibers, quartz fibers and carbon fibers.

EXAMPLES

The following examples are provided for the purpose of furtherillustrating the present invention but are in no way to be taken aslimiting. “Parts” in the examples means parts by weight and “%” means %by weight. Evaluations were made by the following methods.

(1) Specific Viscosity (η_(sp))

A specimen was dissolved in methylene chloride to prepare a solutionhaving a concentration of about 0.7 g/dL, and the specific viscosity ofthe resulting solution was measured at 20° C. with an Ostwald'sviscometer (RIGO AUTO VISCOSIMETER TYPE VMR-0525·PC). The specificviscosity (η_(sp)) was obtained from the following equation.

η_(sp) =t/t ₀−1

t: flow time of a specimen solutiont₀: flow time of a solvent alone

(2) Number Average Molecular Weight (Mn)

50 μl of a solution prepared by dissolving 10 mg of the specimen in 5 mlof chloroform was injected into a GPC measuring device in a clean airatmosphere at a temperature of 23° C. and a relative humidity of 50% tocarry out GPC measurement at a column temperature of 40° C. and a flowrate of 1 ml/min so as to calculate the number average molecular weightof the specimen. Two Resipore (length of 300 mm, inner diameter of 7.5mm) columns which were manufactured by Polymer Laboratories Co., Ltd.and connected in series, chloroform as a moving phase, the EasiCal PS-2standard substance manufactured by Polymer Laboratories Co., Ltd., RI asa detector and chloroform as a developing solvent were used. Themeasuring devices were the L-6000 pump of Hitachi, Ltd., the L-7200 autosampler of Hitachi, Ltd., the L-7300 column oven of Hitachi, Ltd. andthe L-2490 RI detector of Hitachi, Ltd.

(3) Melt Viscosity

The melt viscosity at 600 sec⁻¹ was read from a shear rate/viscositycurve which was obtained by using the capillary rheometer (CapillographModel 1D) of Toyo Seiki Co., Ltd. and changing the measurement speedarbitrarily at a capillary length of 10.0 mm, a capillary diameter of1.0 mm and a measurement temperature of 250° C.

(4) Content of Biogenic Matter

The content of biogenic matter was measured from a biogenic mattercontent test based on a radiation carbon concentration (percent moderncarbon: C14) in accordance with ASTM D6866 05.

(5) Glass Transition Temperature (Tg)

This was measured with the DSC (Model DSC2910) of TA Instruments Co.,Ltd.

(6) 5% Weight Loss Temperature (Td)

This was measured with the TGA (Model TGA2950) of TA Instruments Co.,Ltd.

(7) Moldabiilty

The specimen was molded with the JSWJ-75EIII of The Japan Steel Works,Ltd. to evaluate the shape of a sample plate having a thickness of 2 mmvisually (mold temperature: 80 to 110° C., molding temperature: 230 to260° C.). The criteria are given below.

◯: a silver streak formed by turbidity, cracking, surface sink ordecomposition is not seenX: a silver streak formed by turbidity, cracking, surface sink ordecomposition is seen

Example 1

1,608 parts by weight (11 mols) of isosorbide and 2,356 parts by weight(11 mols) of diphenyl carbonate were injected into a reactor, 1.0 partby weight (1×10⁻⁴ mol based on 1 mol of diphenyl carbonate) oftetramethylammonium hydroxide and 1.1×10⁻³ part by weight (0.25×10⁻⁶ molbased on 1 mol of diphenyl carbonate) of sodium hydroxide aspolymerization catalysts were fed to the reactor, and the reactor washeated at 180° C. under normal pressure in a nitrogen atmosphere to meltall of them.

The inside pressure of the reactor was gradually reduced to 13.3×10⁻³MPa under agitation over 30 minutes while the formed phenol wasdistilled off. After 20 minutes of a reaction in this state, thetemperature was raised to 200° C., the pressure was gradually reducedover 20 minutes, and the reaction was further carried out at 4.00×10⁻³MPa for 20 minutes while the phenol was distilled off and continued byraising the temperature to 220° C. for 30 minutes and then to 250° C.for 30 minutes.

The pressure was then gradually reduced to continue the reaction at2.67×10⁻³ MPa for 10 minutes and at 1.33×10⁻³ MPa for 10 minutes andfurther reduced to 4.00×10⁻⁵ MPa, and then the temperature was graduallyraised to 260° C. to carry out the reaction at 260° C. and 6.66×10⁻⁵ MPafor 1 hour in the end. As a result, a polymer having a specificviscosity of 0.33 was obtained. This polymer had a biogenic mattercontent of 85% and excellent heat resistance and heat stability and wassatisfactory in terms of moldability as a molding material. Theevaluation results are shown in Table 1.

Example 2

1,608 parts by weight (11 mols) of isosorbide and 2,356 parts by weight(11 mols) of diphenyl carbonate were injected into a reactor and apolymer was obtained by polymerizing them in the same manner as inExample 1 except that 1.0 part by weight (1×10⁻⁴ mol based on 1 mol ofdiphenyl carbonate) of tetramethylammonium hydroxide and 2.9×10⁻³ partby weight (0.25×10⁻⁶ mol based on 1 mol of diphenyl carbonate) of sodiumcarbonate as polymerization catalysts were used. This polymer had aspecific viscosity of 0.23 and excellent heat resistance, heat stabilityand moldability. The evaluation results are shown in Table 1.

Example 3

1,608 parts by weight (11 mols) of isosorbide and 2,356 parts by weight(11 mols) of diphenyl carbonate were injected into a reactor and apolymer was obtained by polymerizing them in the same manner as inExample 1 except that 5.7 parts by weight (2×10⁻⁴ mol based on 1 mol ofdiphenyl carbonate) of tetrabutylammonium hydroxide and 1.1×10⁻³ part byweight (0.25×10⁻⁶ mol based on 1 mol of diphenyl carbonate) of sodiumhydroxide as polymerization catalysts were used. This polymer had aspecific viscosity of 0.28 and excellent heat resistance, heat stabilityand moldability. The evaluation results are shown in Table 1.

Comparative Example 1

1,608 parts by weight (11 mols) of isosorbide and 2,426 parts by weight(11.33 mols) of diphenyl carbonate were injected into a reactor andpolymerization was carried out in the same manner as in Example 1 exceptthat 1.0 part by weight (1×10⁻⁴ mol based on 1 mol of diphenylcarbonate) of tetramethylammonium hydroxide and 1.1×10⁻³ part by weight(0.25×10⁻⁶ mol based on 1 mol of diphenyl carbonate) of sodium hydroxideas polymerization catalysts were used. As a result, although thispolymer had a specific viscosity of 0.19 and satisfactory heatresistance and heat stability, cracking occurred during molding. Theevaluation results are shown in Table 1.

Comparative Example 2

1,590 parts by weight (10.88 mols) of isosorbide and 39 parts by weight(0.26 mol) of p-tert-butylphenol were fed to a reactor equipped with athermometer and a stirrer, the inside of the reactor was replaced bynitrogen, and 5,500 parts by weight of well dried pyridine and 32,400parts by weight of methylene chloride were added to dissolve the abovesubstances. 1,400 parts by weight (14.14 mols) of phosgene was blowninto the reactor at 25° C. under agitation over 100 minutes. After theblowing of phosgene, the solution was directly stirred for about 20minutes to terminate the reaction. After the end of the reaction, theobtained product was diluted with methylene chloride, pyridine wasneutralized with hydrochloric acid and removed, the resulting productwas rinsed repeatedly until its conductivity became almost the same asthat of ion exchange water, and methylene chloride was evaporated toobtain an achromatic powder.

As a result, a polymer having a specific viscosity of 0.48 was obtained.However, as this polymer had too high melt viscosity, a silver streakwhich seemed to be caused by decomposition was seen during molding, andthe polymer was colored badly. The evaluation results are shown in Table1.

Comparative Example 3

1,206 parts by weight (8.2 mols) of isosorbide, 628 parts by weight (2.8mols) of bisphenol A and 2,403 parts by weight (11.33 mols) of diphenylcarbonate were injected into a reactor, and a polymer was obtained bypolymerizing them in the same manner as in Example 1 except that 1.1part by weight (1×10⁻⁴ mol based on 1 mol of diphenyl carbonate) oftetramethylammonium hydroxide and 1.1×10⁻³ part by weight (0.25×10⁻⁶ molbased on 1 mol of diphenyl carbonate) of sodium hydroxide aspolymerization catalysts were used. This polymer had a specificviscosity of 0.30 and excellent heat resistance, heat stability andmoldability. However, it was unsatisfactory in terms of the content ofbiogenic matter (63%). The evaluation results are shown in Table 1.

Comparative Example 4

1,125 parts by weight (7.7 mols) of isosorbide, 251 parts by weight (3.3mols) of 1,3-propanediol and 2,356 parts by weight (11 mols) of diphenylcarbonate were injected into a reactor, and a polymer was obtained bypolymerizing them in the same manner as in Example 1 except that 1.0part by weight (1×10⁻⁴ mol based on 1 mol of diphenyl carbonate) oftetramethylammonium hydroxide and 1.1×10⁻³ part by weight (0.25×10⁻⁶ molbased on 1 mol of diphenyl carbonate) of sodium hydroxide aspolymerization catalysts were used. This polymer had a specificviscosity of 0.31 and high moldability but was slightly inferior in heatstability and not satisfactory in terms of heat resistance and thecontent of biogenic matter. The evaluation results are shown in Table 1.Propanediol derived from petroleum was used in Comparative Example 4.

TABLE 1 Unit Ex. 1 Ex. 2 Ex. 3 C. Ex. 1 C. EX. 2 C. Ex. 3 C. Ex. 4Isosorbide Molar 1 1 1 1 1 0.75 0.70 ratio Bisphenol A Molar 0 0 0 0 00.25 0 ratio 1,3-propanediol Molar 0 0 0 0 0 0 0.30 ratio Diphenyl Molar1.00 1.00 1.00 1.03 — 1.03 1.00 carbonate ratio Specific None 0.33 0.230.28 0.19 0.48 0.30 0.31 viscosity Number average None 18300 12800 1560010600 26500 16700 17700 molecular weight Melt viscosity ×10⁻³ Pa · s1.40 0.65 1.03 0.35 2.53 1.07 0.35 (250° C., 600 sec⁻¹) Content of % 8584 85 83 85 63 59 biogenic matter Glass transition ° C. 167 162 166 152172 160 114 temperature 5% weight loss ° C. 357 355 354 354 356 356 332temperature Moldability None ◯ ◯ ◯ X X ◯ ◯ (cracked) (silver streak)Ex.: Example C. Ex.: Comparative Example

Example 4

789 parts by weight (5.4 mols) of isosorbide, 88 parts by weight (0.6mol) of isomannide and 1,285 parts by weight (6 mols) of diphenylcarbonate were injected into a reactor, 0.6 part by weight (1×10⁻⁴ molbased on 1 mol of diphenyl carbonate) of tetramethylammonium hydroxideand 6.0×10⁻⁴ part by weight (0.25×10⁻⁶ mol based on 1 mol of diphenylcarbonate) of sodium hydroxide as polymerization catalysts were fed tothe reactor, and the reactor was heated at 180° C. under normal pressurein a nitrogen atmosphere to melt all of them.

The inside pressure of the reactor was gradually reduced to 13.3×10⁻³MPa under agitation over 30 minutes while the formed phenol wasdistilled off. After 20 minutes of a reaction in this state, thetemperature was raised to 200° C., the pressure was gradually reducedover 20 minutes, and the reaction was further carried out at 4.00×10⁻³MPa for 20 minutes while the phenol was distilled off and continued byraising the temperature to 220° C. for 30 minutes and then to 250° C.for 30 minutes.

The pressure was then gradually reduced to continue the reaction at2.67×10⁻³ MPa for 10 minutes and at 1.33×10⁻³ MPa for 10 minutes andfurther reduced to 4.00×10⁻⁵ MPa, and then the temperature was graduallyraised to 260° C. to carry out the reaction at 250° C. and 6.66×10⁻⁵ MPafor 1 hour in the end. A polymer after the reaction was pelletized toobtain a polymer having a specific viscosity of 0.28. The evaluationresults of this polymer are shown in Table 2.

Example 5

The procedure of Example 1 was repeated except that 851 parts by weight(5.8 mols) of isosorbide and 26 parts by weight (0.2 mol) of isomannidewere used, and the obtained polymer after the reaction was pelletized.The polymer had a specific viscosity of 0.32. Other evaluation resultsare shown in Table 2.

TABLE 2 Unit Example 4 Example 5 Isosorbide Molar ratio 0.9 0.97Isomannide Molar ratio 0.1 0.03 Diphenyl carbonate Molar ratio 1.0 1.0Specific viscosity None 0.28 0.32 Number average molecular weight None15200 17400 Melt viscosity (250° C., 600 sec⁻¹) ×10⁻³ Pa · s 1.05 1.45Content of biogenic matter % 85 85 Glass transition temperature ° C. 164165 5% weight loss temperature ° C. 358 354 Moldability None ◯ ◯

EFFECT OF THE INVENTION

The polycarbonate resin of the present invention shows a high content ofbiogenic matter and has excellent heat resistance, heat stability andmoldability. The polycarbonate resin of the present invention hasexcellent heat resistance with a high glass transition temperature.

The polycarbonate resin of the present invention has excellent heatstability with a thermal decomposition temperature (5% weight losstemperature) higher than 330° C.

According to the manufacturing process of the present invention, apolycarbonate resin having a high content of biogenic matter, excellentheat resistance, heat stability and moldability can be obtained.

INDUSTRIAL APPLICABILITY

The polycarbonate resin of the present invention is useful as a moldingmaterial. The polycarbonate resin of the present invention may be mixedwith a polymer containing biogenic matter such as polylactic acid,aliphatic polyester, aromatic polyester, aromatic polycarbonate,polyamide, polystyrene, polyolefin, polyacryl, ABS or polyurethane,synthetic resin and rubber to be alloyed.

1. A polycarbonate resin containing a recurring unit represent by thefollowing formula (1) as the major constituent, wherein (i) the specificviscosity of a solution prepared by dissolving 0.7 g of the resin in 100ml of methylene chloride at 20° C. is 0.20 to 0.45; (ii) the glasstransition temperature (Tg) of the resin is 150 to 200° C.; and (iii)the 5% weight loss temperature (Td) of the resin is 330 to 400° C.


2. The polycarbonate resin according to claim 1 which contains therecurring unit represented by the formula (1) in an amount of more than98 mol % and 100 mol % or less.
 3. The polycarbonate resin according toclaim 1, wherein the specific viscosity of a solution prepared bydissolving 0.7 g of the resin in 100 ml of methylene chloride at 20° C.is 0.20 to 0.37.
 4. The polycarbonate resin according to claim 1 whichhas a glass transition temperature (Tg) of 150 to 168° C.
 5. Thepolycarbonate resin according to claim 1 which has a number averagemolecular weight (Mn) of 1.2×10⁴ to 2.2×10⁴.
 6. The polycarbonate resinaccording to claim 1 which has a biogenic matter content measured inaccordance with ASTM D6866 05 of 83 to 100%.
 7. The polycarbonate resinaccording to claim 1, wherein the recurring unit represented by theformula (1) is a unit derived from isosorbide.
 8. The polycarbonateresin according to claim 1, wherein the recurring unit represented bythe formula (1) is a combination of 75 to 99 mol % of a unit derivedfrom isosorbide and 25 to 1 mol % of a unit derived from isomannideand/or isoidide.
 9. A process of manufacturing a polycarbonate resin byreacting a diol component (component A) with a diester carbonate(component B), wherein (i) the diol component (component A) contains anether diol represented by the following formula (2) as the majorconstituent,

and the process comprises the steps of: (ii) thermally reacting thesecomponents at normal pressure in the presence of at least onepolymerization catalyst selected from the group consisting of anitrogen-containing basic compound, alkali metal compound and alkaliearth metal compound; and (iii) thermally reacting these components at180 to 280° C. under reduced pressure.
 10. The manufacturing processaccording to claim 9, wherein the ratio of the diester carbonate(component B) to the diol (component A) is 1.02 to 0.98 (B/A).
 11. Themanufacturing process according to claim 9, wherein the diol component(component A) contains a compound represented by the formula (2) in anamount of more than 98 mol % and 100 mol % or less.
 12. Themanufacturing process according to claim 9, wherein the compoundrepresented by the formula (2) is isosorbide.
 13. The manufacturingprocess according to claim 9, wherein the compound represented by theformula (2) consists of 75 to 99 mol % of isosorbide and 25 to 1 mol %of isomannide and/or isoidide.
 14. The manufacturing process accordingto claim 9, wherein the diester carbonate (component B) is diphenylcarbonate.
 15. The manufacturing process according to claim 9, whereinthe polymerization catalyst is a combination of a nitrogen-containingbasic compound and an alkali metal compound.